Container with pressure retaining sealing elements

ABSTRACT

A container with a material-dispensing portion is disclosed where the material-dispensing portion has an opening disposed in a predetermined plane and has an endless surface, said surface being inclined to said plane. The container is in combination with a sheet-like sealing element having a marginal portion bonded to the surface of the container around the opening and having a median portion overlying the opening, the median portion being inclined with reference to the plane of the opening and making therewith an angle which, at most, slightly exceeds the angle between the plane of the opening and the endless surface of the material dispensing portion.

United States Patent Willhaus et a1.

[is] 3,655,084 [451 Apr. 11, 1972 [54] CONTAINER WITH PRESSURE RETAININGSEALING ELEMENTS [72] Inventors: Werner Willhaus, Stuttgart-Kaltental;Friedrich Scharf, Stuttgart-Stammheim,

[21] Appl. No.: 98,350

[30] Foreign Application Priority Data Jan. 30, 1970- Germany ..P 20 04190.1

[56] References Cited UNITED STATES PATENTS 2,783,908 3/1957 Winfield..2l5/37R 3,529,647 9/1970 Ignell ..215/1C FOREIGN PATENTS ORAPPLICATIONS 452,352 3/1913 France .215/38 R 1,074,414 7/1967 GreatBritain ..215/1 C 1,208,401 10/1970 Great Britain ..215/38 R PrimaryExaminer-M. Henson Wood, Jr. Assistant Examiner.Thomas C. Culp, Jr.Attorney-Michael S. Striker [57] ABSTRACT A container with amaterial-dispensing portion is disclosed where the material-dispensingportion has an opening disposed in a predetermined plane and has anendless surface, said surface being inclined to said plane. Thecontainer is in combination with a sheet-like sealing element having amarginal portion bonded to the surface of the container around theopening and having a median portion overlying the open ing, the medianportion being inclined with reference to the plane of the opening andmaking therewith an angle which, at most, slightly exceeds the anglebetween the plane of the opening and the endless surface of the materialdispensing portion.

13 Claims, 2 Drawing Figures CONTAINER WITH PRESSURE RETAINING SEALINGELEMENTS BACKGROUND OF THE INVENTION It is known and common practice toseal containers with a planar sealing plate of metal foil or syntheticresin foil, where SUMMARY OF THE INVENTION It is an object of theinvention to construct a container with a simple seal which can bemaintained against the pressure resulting from the evolution of gas fromliquids.

It is a further object of the invention to construct a container andseal which can retain gas pressure and where the container is made ofsynthetic resin.

In order to achieve the objects of the present invention, the rim aroundthe material dispensing portion of the container and the sealing elementin the neighborhood of the sealing seam between the rim and the sealingelement are inclined at an angle to the plane defined by the rim aroundthe materialdispensing portion of the container. Further, that portionof the sealing element henceforth referred to as a cap, overlying thematerial-dispensing portion of the container, henceforth referred to asthe mouth, also makes an angle with the plane defined by the rim of thecontainer, and the former angle is greater than, equal to, or slightlyless than the latter angle. Stated, conversely, the angle between themedian portion of the cap and the reference plane is, at most, slightlygreater than the angle between the part of the cap in contact with the vrim of the container and the reference plane.

The purpose of the construction modification in accordance with thepresent invention is to change the type of stress to which the bondbetween the closure and the vessel is subjected. In the usualconstruction, failure takes place by peeling in which the bond issubjected to tension over a restricted area which is much smaller thanthe total area of the bond. In contrast, using a dished cap and a bondover an inclined surface, the bond is stressed in shear. With thisdesign, then, it is possible to bond a cap to a container where the bondis to resist the thrust of gas evolved from the liquid content.

The closure element is preferably made of synthetic resin or metal foil,punched and formed in a single operation. In further processing with thehelp of pressure and heat the closure is then sealed over the mouth ofthe filled container.

The novel features which are considered as characteristic for theinvention are set forth in particular in the appended claims. Theinvention itself, however, both as to its construction and its method ofoperation, together with additional objects and advantages thereof, willbe best understood from the following description of specificembodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 shows a container with a capsealed over the top, in cross section; and

FIG. 2 shows in cross section a further example of the method ofclosure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The container 1 which may be abottle, is prepared from thermoplastic synthetic resin by blow molding;it has a neck 2 in which there is a mouth or opening 3 surrounded by acollar 4.

The upper face 5 of the collar 4, which may be viewed as an endlesssurface, has the form as a zone of a sphere. The cap 6 is made of ametal-foil coated with a heat-scalable material and is sealed to thesurface 5. The cap 6 has the form of a cap, the radius of whichcorresponds to the radius of the spherical zone of the collar 4. The cap6 has a tab 7 which extends outward from the outer periphery of the cap.

A variety of 7 physical properties in the closure can be achieved byforming the cap so that it has other curvatures. Examples are thesurfaces prepared by rotating the conic sections, examples beingparaboloids, ellipsoids, and hyperboloids of revolution. The surface 5with which the cap must mate, must also have the appropriate form suchas a zone of a surface obtained by rotating a conic section.

It is essential that the form of the cap 6 and the surface 5 of themouth of the bottle should incline in the region of the seal of thebottle at an angle to the plane as defined by the mouth of the bottlewhich is larger than, equal to, or only slightly less than the angleformed by the bulged-out portion of the cap lying over the mouth of thebottle and the same reference plane. In establishing the angle ofinclination of the surface which is to be sealed, it must be noted thatthe preformed bulge of the closure will be increased as a result of theinternal pressure in the container and the angle of inclination of thebulge at the inner surface of the seal will be increased even more. Theangle of inclination in the region of the seal can either be constant orvariable.

In the example illustrated in FIG. 2, the closure 6 has not merely asingle generated surface, but rather essentially two surface regions,namely a region in the area over the surface 5 which is a frustum of acone and a planar or outwardly bulged zone in the median region. It isalso essential here that the angle of inclination in the region of theseal be not substantially less and preferably greater than the angle ofinclination of the bulge of the cap as it meets the inner portion of theseal.

During transportation the sealed container may be exposed totemperatures up to 40 C. Since the internal pressure will be increasedby the rise in temperature, it is desirable that the cap be made ofmetal foil with a coating which will hold fast at temperatures up to' at50 C., and the softening point of which is over C. Such coatings can beprepared on the basis of polyvinyl chloride-mixed polymer.

It should be noted that the two examples shown in the figures constitutethe presently preferred embodiments of the invention.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featuresthat, from the standpoint of prior art, fairly constitute essentialcharacteristics of the generic or specific aspects of this inventionand, therefore, such adaptations should and are intended to becomprehended within the meaning and range of equivalence of thefollowing claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims.

We claim:

1. Container, particularly bottle, including a materialdispensingportion having an opening disposed in a predetermined plane, and havingan endless surface, said surface being inclined to said plane; and asheet-like sealing element having a marginal portion bonded to saidsurface and a median portion overlying said opening, said median portionbeing inclined with reference to said plane and making therewith anangle which at most slightly exceeds the angle between said plane andsaid surface.

2. Container as defined in claim 1, wherein said container consists, atleast in part of a thermoplastic synthetic resin.

3. Container as defined in claim I, wherein said dispensing portion andsaid sealing element form a circumferentially complete seam located in aplane which is parallel to said predetermined plane.

4. Container as defined in claim 1 wherein said dispensing portion andsaid sealing element form a circumferentially complete and wide seam.

have a shape such as is generated by rotation of a conic sectlon.

8. Container as defined in claim 7 wherein said marginal portion of saidsealing element has the form of a conical frustum.

9. Container as defined in claim 1 wherein the inclination of saidmarginal portion of said sealing element is greater than the inclinationof said median portion.

10. Container as defined in claim 1 wherein said sealing element isconcave-convex, said concave surface facing toward said opening of saidmaterial-dispensing portion.

1 1. Container as defined in claim 1, wherein said sealing elementcomprises a metal foil coated on the surface facing toward said openingof said material-dispensing portion. v

12. Container as defined in claim 1 wherein said sealing elementcomprises a gripping tab.

13. Container as defined in claim 1 wherein said sealing elementcomprises a thermoplastic synthetic resin.

1. Container, particularly bottle, including a materialdispensingportion having an opening disposed in a predetermined plane, and havingan endless surface, said surface being inclined to said plane; and asheet-like sealing element having a marginal portion bonded to saidsurface and a median portion overlying said opening, said median portionbeing inclined with reference to said plane and making therewith anangle which at most slightly exceeds the angle between said plane andsaid surface.
 2. Container as defined in claim 1, wherein said containerconsists, at least in part of a thermoplastic synthetic resin. 3.Container as defined in claim 1, wherein said dispensing portion andsaid sealing element form a circumferentially complete seam located in aplane which is parallel to said predetermined plane.
 4. Container asdefined in claim 1 wherein said dispensing portion and said sealingelement form a circumferentially complete and wide seam.
 5. Container asdefined in claim 1 wherein the inclination of said endless surface andof said sealing element in the region of said marginal portion isconstant.
 6. Container as defined in claim 1 wherein the inclination ofsaid endless surface and of said sealing element in the region of saidmarginal portion is variable.
 7. Container as defined in claim 1 whereinsaid endless surface and said marginal portion of said sealing elementeach have a shape such as is generated by rotation of a conic section.8. Container as defined in claim 7 wherein said marginal portion of saidsealing element has the form of a conical frustum.
 9. Container asdefined in claim 1 wherein the inclination of said marginal portion ofsaid sealing element is greater than the inclination of said medianportion.
 10. Container as defined in claim 1 wherein said sealingelement is concavo-convex, said concave surface facing toward saidopening of said material-dispensing portion.
 11. Container as defined inclaim 1, wherein said sealing element comprises a metal foil coated onthe surface facing toward said opening of said material-dispensingportion.
 12. Container as defined in claim 1 wherein said sealingelement comprises a gripping tab.
 13. Container as defined in claim 1wherein said sealing element comprises a thermoplastic synthetic resin.